65561660 has 12 divisors (see below), whose sum is σ = 137679528. Its totient is φ = 26224656.

The previous prime is 65561653. The next prime is 65561681. The reversal of 65561660 is 6616556.

65561660 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 65561660.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1639022 + ... + 1639061.

It is an arithmetic number, because the mean of its divisors is an integer number (11473294).

Almost surely, 2^65561660 is an apocalyptic number.

It is an amenable number.

65561660 is an abundant number, since it is smaller than the sum of its proper divisors (72117868).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

65561660 is a wasteful number, since it uses less digits than its factorization.

65561660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3278092 (or 3278090 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 35.

The square root of 65561660 is about 8097.0154995529. The cubic root of 65561660 is about 403.2273488498.

The spelling of 65561660 in words is "sixty-five million, five hundred sixty-one thousand, six hundred sixty".